Business Acquisitions - Schedule of Preliminary Allocation of the Purchase Price (Details) (USD $)			0 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Feb. 18, 2014 Prolexic Technologies, Inc.
Business Acquisition [Line Items]
Total purchase consideration			$ 392,104,000
Allocation of the purchase consideration:
Cash			33,072,000
Accounts receivable			11,208,000
Property and equipment			12,225,000
Identifiable intangible assets			87,040,000
Goodwill	1,049,047,000	757,368,000	291,679,000
Deferred tax assets			16,000,000
Other current and long-term assets			5,850,000
Total assets acquired			457,074,000
Other current liabilities			(6,019,000)
Current deferred revenue			(5,812,000)
Deferred tax liabilities			(33,723,000)
Debt, capital leases and other long-term liabilities			(19,416,000)
Total liabilities assumed			(64,970,000)
Net assets acquired			$ 392,104,000